From the state of the art numerous devices and methods are known to develop and arrange gearing parts, which are in gear with each other in such a way that the tooth gear between them is essentially without backlash. Such adjustment devices, which are embodied in a manner free from backlash are advantageous for the relative movement between two parts of a motor vehicle seat, which are to be adjusted, because undesired backlash is practically excluded and noises caused thereof while driving, for example rattling, or mechanical movements, namely for example trembling of a part are mostly excluded. A zero backlash of the two parts of a motor vehicle seat, which are to be adjusted towards each other via an adjustment device is of a special importance, if the path is relatively long between the adjustment device and the place, where a force can act upon. This is the case for example with adjustment devices for the inclination adjustment of back rests. Here, the back rest is a fairly long lever, even a slight backlash in the joint of the adjustment device has an effect at the end of the back rest over the entire length of the lever.
The possibilities for compensating the backlash for adjustment devices of the kind mentioned here allow a compensation of the backlash over the entire adjustment path, which the two parts to be adjusted move along in a relative manner towards each other. The compensation of the backlash, however, has the disadvantage that the operational forces for the adjustment device also have to have an effect on the compensation for the backlash at the same time, namely moving the same at least partially or surmount it. The adjusting forces are therefore higher than with adjustment devices without a compensation of the backlash. Especially with manual adjustment devices a certain disadvantage is obvious, as higher operational forces are required.